Thicknet

Denotes a coaxial cable type (similar to RG-8) that is commonly used with Ethernet (10Base-5) backbones. Originally, thicknet cabling was the only cabling type used with Ethernet, but it was replaced as backbone cabling by optical fiber cabling. Thicknet cable has an impedance of 50 ohms and is commonly about 0.4 inches in diameter.